Pontoon structure for airplanes



Dec. 17, 1946. E. WEISSMAN 2,412,193

PONTOON STRUCTURE FOR AIRPLANES Filed Dec. 27, 1944 2 Sheets-Sheet 1 J3 I 'IIIIIII/IIII.

1946- E. WEISSMAN 2,412,79

PONTOON STRUCTURE FOR AIRPLANES Filed Dec. 271-1944 2 Sheets-Sheet 2 Patented Dec. 17, 1946 UNITED STATES PATENT OFFICE PONTOON STRUCTURE FOR AIRPLANES Eugene Weissman, Baltimore, Md. Application December 27, 1944, Serial No. 569,951

Claims. (01. 244-102) This invention relates to pontoon structure for airplanes.

The invention is more particularly concerned with a pontoon adapted for use with airplane wings and wherein it is swingably supported by a wing for retraction to an inoperative position within the wing and for protraction to an operative position in depending relation to the wing. The pontoon is furthermore inflatable and, expansible when moved to the operative position and deflatable and collapsible when moved to the inoperative position.

The pontoon structure is substantially as disclosed in my co-pending application, Serial No. 456,983, filed September 2, 1942, and of which the present application is a continuation in part.

The present invention further includes means for alternately protracting the pontoon to an operative position externally of a plane wing while expanding and inflating same, and retracting the pontoon to an inoperative position within the wing while collapsing and deflating same.

It is appreciated that diversified forms of pontoons for use with airplanes have heretofore been proposed or used and which in certain instances were retractible and protractible; in some instances they were collapsible and expansible, and also in some instances they were inflatable and deflatable.

In such prior pontoon arrangements, however, these several desirable features were not embodied in a structure in such manner as to render the several operations in automatic sequence with a minimum of effort on the part of a pilot.

It is accordingly a primary object of the present invention to provide a pontoon arrangement of the above noted general character which substantially overcomes objections to prior pontoon arrangements, with the provision of one which more fully meets the requirements of such structures.

A further object of the invention is the provision of a pontoon structure having pivotal connection with the lower wall of an airplane wing for alternate retraction through an opening in such wall to an inoperative position within the wing and for protraction to an operative position in depending relation to the wing, and wherein the pontoon is expanded and inflated when moved to the operative position and collapsed and deflated when moved to the inoperative position.

A still further object of the invention is the provision of a pontoon of. such construction that 2 it will offer minimum air resistance when in operative position in depending relation to the wing.

-A still further object of the invention is the provision of a pontoon which is relatively light in weight, simple in construction, durable, and eflicient in operation.

Other andfurther objects of the invention will become more apparent as the description proceeds, when taken in connection with the accompanying drawings, wherein a Figure 1 is a longitudinal vertical section of the improved pontoon in a preferred physical embodiment thereof and showing the pontoon in expanded and inflated condition.

Fig. 2 is a fragmental view similar. torFig. 1 but showing the pontoon in collapsedand de fiated condition,

Fig. 3 is a broken perspective view of the pontoon.

Fig. 4 is an edge view of an end portion of an airplane wing showing the pontoon in protracted operative position.

Fig. 5 is a longitudinal vertical section of an airplane wing showing the improved pontoon arrangement in operative association therewith, the upper and lower walls of the wing only being shown for clarity of illustration.

Fig. 6 is a vertical transverse section in the plane of line 6--6, Fig. 5.

Fig. 7 is a sectional view of a valve for use in connection with an airsupply and for operation by a pilot.

Fig. 8 is a view similar to Fig. 5 with certain parts omitted and showing a modification of the invention. v

Referring now in detail to the drawings and first to Figs. 1, 2 and 3, P designates the pontoon in its entirety and which comprises a shell or casing In which, as more particularly illustrated in Fig. 3, is stream-lined for minimum air resist.- ance and which casing includes a top wall H. The casing It is preferably beaded at I2 at its lower open end to avoid chafing of a flexible airimpervious member l3 whose upper edge is suitably secured, as at 14, to the lower face of a follower plate I5, and whose lower edge is suitably secured, as at IE, to theupper face of a skimmer plate IT.

A pair of vertically disposed guide rods 18 have their lower ends suitably secured in or to the skimmer plate and the rods extend freely through apertures in the follower plate l5 and the top plate H, and theupper ends of the rodsare turned towards each other and provided with apertured for passage of the rods I8 therethrough j and the upper plates 2!, 22 slidably receive the rods as will appear later. The rods- !8 are preferably provided with stops E8 to limit down ard movement thereof.

A tubular member 25 is suitably secured, as at 26, to the plate i l and extends freely through an. aperture in the follower plate I5. The lower plate 22 is provided with an aperture 2! for receiving the lower end of the tubular member, as in Fig. 2, and the tubular member is preferably provided with a gasket 28 to avoid leakage of air between sameand the wall of the receiving aperture in the follower plate when the pontoon is inflated, as in Fig. 1.

i The flexible member G3, in conjunction with the follower plate 15 and skimmer plate I7, pro- Vides an air chamber C into which air is admitted through the tubular member and from which air is exhausted through the tubular member in a. manner later to appear.

As indicated in Fig. 1, the pontoon P is expanded with the chamber '0 inflated and in which 30 secured to wall I I and the lower wing wall adjacent an edge of an opening 3| in such wing wall.

For effecting swinging movement of the pontoon on its pivot from retracted inoperative position within the wing indicated in dot-and-dash lines in Fig. 5 to a protracted operative position in "depending relation to the wing as indicated in full lines in Fig. 5, and'vice-versa'the tubular member 25 is preferably utilized for imparting effort to the pontoon.

Accordingly, the upper end of the tubular member 25 is provided with a pair of diametrically opposed pins 32 which pivotally engage the bifurcated end '33 of a link 34 whose opposite end is pivotally connected at 3-5 to the free end of a piston rod 3t-proje'cting from a piston 3'! through the end wall of 'a piston-receiving cylinder 38.

With this arrangement, reciprocation of the piston 31 from the full line position in Fig. 5 to the dot-and-dash line position will swing the pontoon 'P to the inoperative retracted position, and vic'e-versa.

In 'order to effect collapsing and alternate expansion of the -pontoon when retracted and protracted respectively, a pair of laterally spaced "cam tracks 39 are rigidly supported within the wing'vv'by'means of 'suitable'bra'c'es 4B. The cam tracks are of substantially 'U-shape in cross section and receive the follower rollers 19 on the rods I8 .and, as indicated in Fig. 5, the cam tracks extend upwardly and to the 'ri'ght'at such "angle and to such extent as to collapse the pontoon sufficiently in advance of its entering the opening 3| in the wing wall, which is of a length approximately equal to the length or heighth of the collapsed pontoon. The tracks 39 thereafter extend concentrically with the pivot 39 in maintaining the rods I8 in raised position with the pontoon collapsed.

To provide for movement of the piston 31 towards opposite ends of the cylinder 38 in retracting and protracting the pontoon, air under suitable pressure is alternately admitted to opposite ends of the cylinder and vented from the opposingends, and for such purpose an air supply conduit 4l communicates at one end with each-end of the cylinder and the opposite ends of the conduits communicate with a rotary valve 42, which includesa fixed outer member 43 to which the conduits are connected. and an inner rotatable member 44. The outer member is provided with a vent aperture 45 and the inner member is provided with a channel 46 and an aperture 41 communicating with the air admission central aperture 48. The valve structure is such that the conduits maybe successively placed in communication with the air aperture 48 with the other vented through the aperture 45. The valve 42 should, of course, be positioned accessibly toa pilot and may be in connection with a suitable air supp y.

In order to inflate the chamber C uponprotraction of the pontoon, the cylinder 38 is provided with an aperture 49 which is closed by the piston 3'! except when the piston has moved to the left in Fig. 5 with the pontoon substantially protracted, and an air conduit 50 communicates with the aperture 49 and an aperture 51 adjacent the upper end'of the tubular member 25 for inflating the chamber C when the pontoon has been protracted and expanded.

The valve 42 may be in association with a pressure gauge which will fluctuate and thus warn the pilot of complete protraction and inflation. However, the valve need not be shut off when the pontoon is protracted or retracted, and preferably should not be. j y

In order to deflate the chamber C upon retraction and collapsing of the pontoon the tubular member 25 is provided with a suitable air release valve 52, including an upwardly springurged head 53 which, when depressed, will permit escape of air from chamber C. Accordingly a cam plate 54 is suspended from the top of the wing by a pair of arms 5'5 Which are at their 0pposite ends pivotally connected to the plate and a support 55; The arms are restrained against swinging movement to the right of their vertical position by means of stop pins 51, with the result that the valve head 53 will be forced downwardly and the air allowed to escape from chamber '0 upon retraction of the pontoon. The cam "plate 54 is, however, free to swing to the left in Fig. 5, and accordingly valve 52 will remain closed during inflation of the chamber C.

A modification of the invention is shown in Fig. 8, wherein the cylinder 38 is pivotally connected at 59 to a bracket 69 secured to the wing, and accordingly the piston rod 36 may be directly connected to the tubular member 25 in the absence of'the link 34. '1

It is, of course, to be understood that'a similar pontoon will be used on an opposing wing of an airplane provided with any desirable form of body pontoon supportingmeans. v

A suitable yieldable catch may be provided as an aid in retainingthe pontoon against inadver- "tent movement from within the wing, and such catch may include a skimmer plate engaging member BI urged toward opening 3| by a spring '62 surrounding a rod -63 movable in a rigid support 64 Such catch, however, may be omitted since the pontoon would remain in inoperative position against the air pressure within the cylinder 38. Since the pontoon P is pivotally supported at a point offset from its vertical center plane, a tendency would exist to move the pontoon toward inoperative position when the weight of the wing is on the pontoon. However, such tendency is resisted by the air pressure against the right-hand end of the piston 31 as well as by the inflated chamber C which exerts a downward pressure on the skimmer plate and accordingly on the rods l8, which must be raised in movement of the pontoon toward its retracted position.

It will be observed from the foregoing disclosure that the pontoon P is highly adaptable for use with airplane wings due to the stream-line contour of the casing, with consequent minimum air resistance, the collapsing and retracting of the pontoon within the win when not in use and the protracting, expanding and inflation of the chamber C when the pontoon is in use.

The operating means for effecting the different movements of the pontoon as well as for inflating and deflating the chamber C are simple in construction and operative through a single control valve, and while I have disclosed but a single epecific operative embodiment of the pneumatic operating means, it is to be understood that variations therein may be resorted to Within the scope of the claims.

What I claim and desire to secure by U. S. Letters Patent is:

1. A collapsible and expansible pontoon comprising a casing having a closed top and an open bottom, a skimmer plate below said casing, a pair of vertically disposed rods having their lower ends secured to the skimmer plate and extending freely through apertures in the top of the casing, a follower plate within the casing freely movable on said rods, a flexible air-impervious member interconnecting the skimmer and follower plates and providing therewith an air chamber and means for limiting movement of the rods and skimmer plate in the collapsed and expanded condition of the pontoon.

2. A pontoon according to claim 1, together with bracing members supported by said closed top and said skimmer plate and each including vertically spaced plates having apertures through which said rods extend.

3. A pontoon according to claim 1, together with a tubular member extending through and secured to said casing top, the tubular member projecting above and below said top and the lower end thereof projecting freely through an aperture in the follower plate.

4. An expansible and collapsible pontoon comprising a casing for pivotal connection with the lower wall of an airplane wing, the casing opening downwardly and having a closed top, a skimmer plate disposed below the casing, a pair of guide rods having their lower ends secured to the skimmer plate and extending freely through apertures in the casing top, a follower plate disposed within the casing through which said rods freely extend for relative vertical movement between the Plate and rods, an air-impervious member connecting the skimmer and follower plates and providing therewith an airchamber, means for admitting air to and discharging same from said chamber, and means for limiting downward and upward movement of the rods and skimmer plate secured thereto in the expansion and collapsing of the pontoon with the air chamber inflated and deflated respectively.

, 5. A pontoon according to claim 4, wherein said air admitting and discharging means comprises a tubular member extending through and secured to the casing top, the lower end of the tubular member projecting freely through an aperture in the follower plate, and link engaging pins on the upper end of the tubular member for movement of the pontoon about its pivotal connection with the airplane wing.

6. A pontoon according to claim 4, wherein the means for limiting upward movement of the rods comprises bracing members secured to thecasing top and skimmer plate and each including vertically spaced plates having apertures through which the rods extend.

7. An expansible and collapsible pontoon comprising a casing having a closed top and an open lower end, a skimmer plate disposed below the casing, a pair of vertical guide rods having their lower ends secured to the skimmer plate and freely movable through the casing top, a follower plate within the casing and freely vertically movable on the rods, a flexible air-impervious member interconnecting the skimmer and follower plates and providing therewith an inflatable and deflatable chamber, means for admitting air to and discharging same from said chamber in the inflation and deflation thereof, means for vertically moving said rods for expanding and collapsing the pontoon with the air chamber inflated and deflated respectively, and means for limiting movement of the rods thereby determining the range of expansion and collapsing of the pontoon.

8. A pontoon according to claim 7, wherein said last means comprises a collar on each of the rods for abutment with the casing top in theexpanded condition of the pontoon, and braces secured to the skimmer plate and easing top and each including a plate through which the rods extend, with said plates engageable with opposite faces of the follower plate in the collapsed condi tion of the pontoon.

9. In combination with an airplane wing having an opening in the lower wall thereof, a pontoon comprising a casing having an open end and a closed end pivotally secured to said wall adjacent one edge of said opening, said pontoon further comprising a skimmer plate, a pair of guide rods having corresponding ends secured to the skimmer plate and freely movable through apertures in the closed casing end, a follower plate within the casing freely movable along said rods, a flexible member interconnecting the skimmer and follower plates and providing therewith an air chamber, a tubular member secured to the closed casing and freely projecting through said follower plate into said air chamber, means limiting movement of the. skimmer plate relative to said closed casing end, and meanswithin the wing and operative by a pilot for successively swinging said pontoon about its pivot from an inoperative position within the wing to an operative position in depending relation to the wing, expanding the pontoon by movement of the skimmer plate through the rods away from the casing and inflating the air chamber by admission of air through said tubular member, and vice-versa.

withinthe cylinder and having a rod projecting through an end thereof, a, connection between said rod and .said tubular member .for swinging vthe pontoon upon movement of the piston from one end-to the other of thecylinder, cam means -formoving said skimmer plate supporting rods upon swinging movement of the pontoon, an air conduit connecting .saidicylinder. andsaid tubular member to admit air to the chamber uponmovement of the pontoon to-operative vposition, means for exhausting vair from the chamber upon .movement of the pontoon to inoperative position,@.and

valve means for controlling admission of-airto opposite ends of the cylinder andnorresponding venting of the opposed ends.

EUGENE WEISSMANQ 

